Menampilkan postingan dari Desember, 2019

GRX Rear Derailleur: RD-RX815 vs RD-RX817

For the new GRX groupset, there are a total of 4 derailleurs, as shown in the picture below. There are 2 mechanical rear derailleurs and 2 Di2 (electronic shifting) rear derailleurs.

The 4 types of GRX rear derailleurs available.
I am using the GRX RD-RX815 Di2 rear derailleur on my Canyon Endurace for gravel riding, and you can read all about it here. Let me just explain briefly what are the differences between these rear derailleurs.

There is a 1x11 and 2x11 speed spec. The 1x11 speed spec has a shorter cage, and a greater slant angle, in order to shift across the wide ratio cassette (up to 42T sprocket). The 1x11 speed spec cannot be used for front double systems, as the chain capacity is insufficient. This 1x11 speed spec is very similar to the MTB version of Di2 rear derailleur (such as Deore XT RD-M8050), as it is used for wide ratio MTB cassettes.

On the other hand, the 2x11 speed spec is quite similar to road rear derailleurs, like the Ultegra RD-R8050. It has a longer cage to cat…

Polygon Cozmic CX3.0: Shimano XTR M9100 1x12 Speed Drivetrain

I have been trying out different 12 speed groupsets on my Polygon Cozmic CX3.0 MTB, just to compare and feel the differences between them.

The S-Ride 1x12 speed was the first one to be tested, as it was the only upgrade available at that time (August 2018), because SRAM NX Eagle was not available yet. After that, the SRAM NX Eagle 1x12 speed upgrade kit was tested.

Finally we move on to the XTR 1x12 speed setup, which should work better than the other two 12 speed groupsets as it is the top of the range MTB groupset from Shimano. Let's try it out and see how it goes.

XTR RD-M9100 12 speed rear derailleur
There is no longer an extra adapter on the rear derailleur, like other Shadow type rear derailleurs.
Clutch mechanism, with the lever to turn it on and off.
Cable fixing bolt at the inner link of the rear derailleur.
View of the cage set. The guide pulley has a big offset from the rotation axle of the cage set, so that it can reach the larger sprockets of the cassette.
The 51T marking on …

Shimano RX8 Gravel Shoes

As you may have realized from reading this blog that I am quite into gravel riding these days. The general idea of gravel riding is to ride light off-road trails on a road bike, and you can read a more detailed description here.

For gravel riding, most riders that use cleats will use SPD type of cleats, which are used for MTB and off-road riding. SPD-SL cleats which are for road bikes are hardly used for gravel riding, as the ability to walk properly is greatly compromised. Here is an article that I wrote some years back, but it is still as relevant. SPD-SL pedals and cleats also clog up more easily with mud, which will prevent you from clipping in normally.

I like to use SPD cleats and shoes, even on my road bike, as I want to be able to walk normally even when I am off the bike. I cannot do that if I use SPD-SL road shoes. Therefore, all my bikes either have a dual-sided SPD pedal such as the PD-M9020 or a SPD/flat dual sided pedal, such as the PD-A530.

The downside of using SPD shoes …